1. FIELD OF THE INVENTION
The present invention relates to a roll feed apparatus for feeding a plate material held between a pair of rolls intermittently by a predetermined length each time into a production machine such as a press, or more in particular to a roll feed apparatus comprising component parts with mechanisms numerically controlled according to an electrical control circuit for feeding a plate material directly without manual operation.
2. DESCRIPTION OF THE RELATED ART
The same applicant suggested earlier a roll feed apparatus for feeding a plate material held in a pair of rolls intermittently by a predetermined length each time into a production machine such as a press, in which the plate material can be accurately set in position (Japanese utility model application No. 59639/87, U.S. Ser. No. 130,848). This roll feed apparatus comprises a material thickness adjusting mechanism for adjusting the distance between upper and lower rolls in accordance with the thickness of the plate material, a holding power adjusting mechanism for adjusting the power of the upper and lower rolls holding and feeding the material, and a feed length adjusting mechanism for adjusting the length of the material fed.
In the above-described conventional roll feed apparatus, the material thickness, the holding power and feed length are directly adjusted manually by the operator visually watching the indication on a plurality of counters included in and operatively interlocked with the adjusting mechanisms respectively. An apparatus has also been suggested conventionally in which a small motor supports this manual operation to facilitate the adjusting work. Generally, however, the burden on the operator has been considerably heavy, and the fact that the adjusting work generally depends on the ability of each operator has caused undesirable variations in adjustment.